Electrical connection means for multiple bulk compounding systems

ABSTRACT

A device for connecting two or more bulk compounding systems for mixing hyperalimentation solutions is described. The device allows electrical signals from each bulk compounding system to be connected to one another so that each bulk compounding system may act in concert with other bulk compounding systems to fill an individual receiving container with minimal modifications to the internal circuitry of an individual bulk compounding system.

BACKGROUND OF THE INVENTION

The present invention pertains to systems for transferring preciseamounts of fluid solutions at high speeds, and more particularly tomeans for coupling two or more of such systems together. Such systemsare especially useful for the compounding of hyperalimentationsolutions.

As background information, hyperalimentation therapy is the intravenousfeeding of, for example, a protein-carbohydrate mixture to a patient. Itis used primarily to meet the patient's protein and caloric requirementswhich are unable to be satisfied by oral feeding. The protein may be inthe form of free-amino acids or protein hydrolysate and the carbohydratecommonly is dextrose. In addition to the protein and carbohydrate,vitamins (water-soluble and fat-soluble) and electrolytes also can besupplied in this therapy.

Each of these parenteral ingredients and the combination thereof areparticularly susceptible to the growth of deleterious organisms and itis desirable that they be administered to the patient in a sterilecondition. Thus, because these protein and carbohydrate solutions cannotbe pre-compounded by the manufacturer, but must be combined at the timeof their use, their compounding must be performed under sterileconditions to avoid organism growth.

U.S. Pat. No. 4,513,796 to Miller et al. describes a bulk compoundingsystem in which multiple solutions are transferred from separate sourcesto a single container. The system includes a controller that surveysvarious process conditions and warrants of any failure of thoseconditions. Each source of solution is in fluid communication with thecontainer through independent flexible tubing. Fluid flow through thetubing is controlled by multiple peristaltic pumps.

It has been known in the past that to ensure sterility during thecompounding of hyperalimentation solutions, compounding should beperformed under a laminar flow hood. Laminar flow hoods are used forreducing the risk of airborne contamination of such solutions. Theseunits operate by taking room air and passing it through a pre-filter toremove gross contaminates, such as dust and lint. The air is thencompressed and channeled through a bacterial retentive filter in thehood in a laminar flow fashion. The purified air flows out over theentire work surface of the hood in parallel lines at a uniform velocity.The bacterial retentive type of filter is designed to remove allbacteria from the air being filtered.

Compounding under a laminar flow hood aids in preventing airbornecontamination, but it is relatively cumbersome and expensive and wouldnot be useful for eliminating any other source of contamination, such ascontamination caused by handling. When using a hood, the operator mayinadvertently perform the work at the end or outside of the hood and notwithin the recommended space, at least six (6) inches within the hood,which insures the benefits of the air being purified. Time must be takenand care must be exercised to maintain a direct open path between thefilter and the compounding area. Solution bottles and other non-sterileobjects cannot be placed at the back of the hood work area next to thefilter because these objects could contaminate everything downstream anddisrupt the laminar flow pattern of the purified air. Also, in using alaminar flow hood, it is necessary routinely to clean the work surfaceof the hood before any compounding is performed.

As can be seen from the above discussion, it is very important that anyequipment designed to be used under a laminar flow hood does not disruptthe laminar flow of air across the equipment at any location of theequipment which is important to keep sterile. For example, in thesituation in which hyperalimentation solutions are compounded under alaminar flow hood, any connectors between the solution source bags andthe container to be filled with hyperalimentation solution must becarefully designed so that laminar flow at the connection points ismaintained. A particularly critical junction with respect to bulkcompounding systems for producing hyperalimentation solutions is thejuction between the container to be filled and a manifold which receivesall the tubing from the source containers. The present invention takesinto consideration this need for maintaining laminar flow across such ajunction and, in addition, provides a relatively simple means ofcombining two or more bulk compounders of the type described in U.S.Pat. No. 4,513,796 together to enable a user to compound a wider varietyof solutions.

OBJECTS OF THE INVENTION

An object of the subject invention is to provide a means for combiningtwo or more bulk compounding systems together to allow a user tocompound a greater number of fluids.

Another object of the subject invention is to provide a means forelectrically interfacing two or more bulk compounding systems so that auser is able to cause fluids controlled by a number of bulk compoundingsystems to be transferred into a single container.

Another object of the subject invention is to provide a manifold forreceiving multiple sets of tubing from different bulk compoundingsystems for fluid transfer into a single container in which the manifoldincludes an outlet port which can be situated to be exposed to laminarair flow.

Yet another object of the subject invention is to provide an economicmeans for providing a highly flexible device for compounding a widevariety of fluids into a single container.

Other objects, advantages, and novel features of the present inventionwill become apparent from the following detailed description of theinvention when considered in conjunction with the accompanying drawings.Before explaining the embodiments of the invention in detail, it is tobe understood that the invention is not limited in its application tothe details of the construction and to the arrangement of components asset forth in the following description, or as illustrated in theaccompanying drawings. The invention is capable of other embodiments andof being practiced and carried out in various ways. Furthermore, it isto be understood that the phraseology and terminology employed are forthe purpose of description and should not be regarded as limiting.

SUMMARY OF THE INVENTION

The subject invention can be described as a means for connectingmultiple bulk compounding systems together in which each compoundingsystem precisely controls fluid transfer of at least one solution to acontainer. Each bulk compounding system includes a plurality of solutionsources for containing a plurality of individual solutions. A manifoldis used to connect individual fluid lines from each of the fluid sourcesto a manifold which is in fluid communication with the receivingcontainer. Each bulk compounding system includes a pumping means forpumping fluid in each of the individual fluid lines. In accordance withthe invention, a control means is provided which includes a first meansfor sensing the weight of fluid in a container, and a peripheralinterface unit. The peripheral interface provides a first set of inputsignals for selecting an amount of fluid to be transferred from eachsource to the receiving container. The peripheral interface unit alsoprovides a first set of output signals for displaying the amount ofsolution to be transferred, and a second set of output signals forcontrolling the pump means to deliver a predetermined amount of solutionfrom each source to the container in response to the amount of fluidssensed in the container.

In accordance with the invention, a connector means is provided forconnecting the second set of output signals from each of the bulkcompounding systems to allow multiple bulk compounding systems to act inconcert to fill a single receiving container. The connector meansincludes a multiplexer means for receiving the second set of outputsignals from the control means of each bulk compounding system, and forgenerating a plurality of output signals to activate specific portionsof the pumping means to control flow of fluid from each of the solutionsources into the container.

The invention also includes the use of another connector means forconnecting the first set of output signals from the controller means ofeach bulk compounding system to generate a plurality of output signalswhich display the specific amount of fluid to be transferred from eachsource to the container.

In one embodiment of the invention, a novel manifold is provided forconnecting a plurality of inlet lines into a single outlet line. Themanifold includes a cylindrical housing having a first plurality ofradially extending input ports in a first plane, and a second pluralityof radially extending input ports in a second plane. The first andsecond planes may have an intersecting angle ranging from 60° to 120°.The housing also includes a single axially extending output port.

The invention includes the novel feature that pumping modules for eachbulk compounder may be placed one above the other, yet vertically spacedapart from each other to enhance laminar flow along the sides of eachmodule when placed under a laminar flow hood having air flowing from theback to the front of each pumping module. In one embodiment of theinvention, the manifold described above may be attached to one of thepumping modules so that the axially extending outlet port is orientedgenerally toward the back of the pumping module. The placement anddesign of the manifold is such that laminar air flow is present acrossthe critical outlet port of the manifold.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a single bulk compounding system;

FIG. 2 is a front view of a single control panel for a bulk compoundingsystem;

FIG. 3 is a schematic block diagram of a single bulk compounding system;

FIG. 4 illustrates two pumping modules of two separate bulk compoundingsystems working together to fill a single receiving container;

FIG. 5 is a front view of a control panel for two or more bulkcompounding systems connected to each other;

FIG. 6 is an isometric view of a manifold in accordance with theinvention;

FIG. 7 is an isometric view of a manifold attached to a pumping modulewith the outlet port of the manifold oriented to enhance laminar flow;

FIG. 8 illustrates a top view of an alternative embodiment of themanifold of FIG. 6 for use with four separate compounding systems;

FIG. 9 is a cutaway view of a manifold illustrating the fluidconnections between the multiple inlet ports of the manifold to thesingle outlet port of the manifold;

FIG. 10 is a block diagram illustrating the electrical connections forthe input signals of two or more bulk compounding systems used inconjunction with each other;

FIG. 11 is a block diagram illustrating the electrical connections formultiple sets of output signals from two or more bulk compoundingsystems for controlling each of the pumping modules for each bulkcompounding system;

FIG. 12 is a schematic diagram of the block diagram in FIG. 11;

FIG. 13 is a block diagram illustrating the electrical connections formultiple sets of output signals from two or more bulk compoundingsystems to display the precise amount of fluids transferred by each bulkcompounding system to a receiving container; and

FIG. 14 is a schematic diagram of the electrical diagram in FIG. 13.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIG. 1, a single bulk compounding apparatus 10 isillustrated. A single bulk compounding system will be first described indetail and then the various features of the present invention whichinvolve coupling two or more bulk compounding systems together will bedescribed.

The single bulk compounding system delivers sterile solutions containedin supply containers 12, 14 and 16 respectively to a sterile receptacleor collection container 18. A flexible plastic container used inaccordance with this invention is one marketed by Travenol Laboratories,Inc. of Deerfield, Ill. under the registered trademark VIAFLEX.

The apparatus 10 delivers the sterile solutions to be compoundedsequentially from the supply containers 12, 14 and 16 to the collectionor receiving container 18 by means of peristaltic pumps 20, 22 and 24.The pumps 20, 22 and 24 are operatively controlled by data entered in acontroller 26 and the information transmitted to the controller 26 by aload cell 28.

The controller includes a first means for sensing the weight of fluid inthe container. This means will be described in greater detail below. Inaddition, the controller includes a second means having a peripheralinterface unit. The peripheral interface unit generates a first set ofinput signals for selecting an amount of fluid to be transferred fromeach supply container 12-16 to the receiving container 18. Theperipheral interface unit also generates a first set of output signalsfor displaying the amount of solution to be transferred. This displayfunction will also be described in greater detail below. Finally, theperipheral interface unit generates a second set of output signals forcontrolling peristaltic pumps 20-24 to deliver a predetermined amount ofsolution from the supply containers 12-16 to the receiving container 18.

In a single system, the supply containers 12, 14 and 16 and thecollection container 18 are supported vertically above a housing 30 by abracket 32. However, the bracket 32 is not used in the preferredembodiment of the invention when two or more bulk compounding systemsare used in conjunction with each other as described more fully belowwith respect to FIG. 4.

In a single system, the housing 30 provides an enclosure for pumps 20,22 and 24 and has a housing door 34 movable for easy access to the pumps20, 22 and 24 for loading, servicing and maintenance thereof. Thehousing door 34 also serves as a protective cover during operation ofthe pumps.

The supply container 12 is coupled with the collection container 18 byflexible tubing 36. The flexible tubing 36 enters the housing 30 atinlet 38 and is placed around rollers (not shown) of the peristalticpump 20. The flexible tubing 36 can be connected to another portion offlexible tubing (not shown) for placement around the rollers of theperistaltic pump. The tubing 36 then exits the housing 30 at outlet 40and enters a junction block 42 coupled to the collection container 18.The junction block 42 provides a channel through which solutions beingpumped through a flexible tube can flow to the collection container 18.

The peristaltic pump 20, in operation, transfers the sterile solution inthe supply container 12 to the collection container 18 by movement ofthe rollers (not shown) in the pump 20. This movement causes acompression of the walls of the flexible tubing 36 forcing the solutiontherein forward in a capillary type action. Retainers 44 and 46 areplaced around the flexible tubing 36 at its entrance to and exit fromthe housing 30 to keep the tubing 36 in place during the operation ofthe pump 20.

The supply container 14 is coupled with the collection container 18 bythe flexible tubing 48. The sterile solution in the container 14 isdelivered to the container 18 by the peristaltic pump 22 in a similarfashion to the fluid delivery from container 12 caused by the pump 20.The flexible tubing 48 also has retainers 50 and 52 placed in a similarmanner to the retainers 44 and 46 of the flexible tubing 36. The supplycontainer 16 is coupled with the collection container 18 by flexibletubing 54 with the peristaltic pump 24 therebetween. The tubing 54 hasretainers 56 and 58 identical in placement and purpose to the retainers44, 46, 50 and 52.

The controller 26 has a control panel 60 as best seen in FIG. 2. Thecontrol panel 60 has a twelve character keyboard 62 consisting of digits0 through 9, a recall key and a clear keyboard key. Each of the supplycontainers is associated with, on the control panel 60, a volume to bedelivered display 70, 72 and 74; a volume to be delivered entry switch78, 80 and 82 for entering respective volume information; a specificgravity display 84, 86 and 88; and a specific gravity entry switch 90,92 and 94 for entering respective specific gravity information.

To enter the desired value for the volume to be delivered to thecollection container 18 from the supply container 12, for example, thevolume to be delivered switch 78 is depressed. The volume display 70then flashes as the desired volume is entered by depressing theappropriate keys of the keyboard 62. The entry of the desired volume isviewed on the volume display 70, and if correct, the volume isregistered by depressing switch 78 again or by depressing the nextdesired entry switch. During entry of the volume information, a light 75is illuminated informing the operator that the units being entered arein milliliters. Further, as each value for volume is registered, thecumulative total can be displayed in the display 102. If the volumeentered is incorrect, the clear button 76 on the keyboard 62 isdepressed to erase the volume previously entered and the correct volumeis then entered and registered in accordance with the above-describedprocedures.

Once all the volume information has been entered an registered and thecontainers connected, the apparatus 10 can be operated. By depressingSTART/RESTART switch 100, the compounding operation begins, the volumeto be delivered displays 70, 72 and 74 are zeroed automatically andcount up as the volume of each solution is delivered one solution at atime to the collection container 18. The volume information will beretained on the displays until the container 18 is removed. The totalvolume to be delivered display 102 also will be zeroed automatically andregister as the solutions are delivered to provide cumulative volumeinformation which is indicated by light 75 being illuminated. Theinformation likewise will be retained until removal of the container 18occurs.

The controller 26 also includes internal electrical checks to monitorvarious electrical components as well as the amount per unit timefunctions of the device. In the event of a malfunction of one of theseconditions, the compounder will cease operations and device alarm light96 will be illuminated. These operating functions have been selected tobe non-fixable by the operator and, therefore, the compounder will notallow a restart until properly serviced.

FIG. 3 depicts, in block form, how volume and failures of predeterminedoperating conditions are sensed and interpreted in a single bulkcompounding system. The controller 26 receives information from loadcell 28 and directs electrical current through electrical connector 110(FIG. 1) to drive the pumps 20, 22 and 24. After the desired volume andspecific gravity information has been entered and registered, switch 100is depressed to state the compounding operation. In operation, thecontroller 26 activates the pump 20 which continues pumping until theweight sensed by load cell 28, of the container 18, corresponds to theamount registered in the controller 26.

An analog-to-digital converter 112 converts the analog signal of theload cell 28 to a digital signal readable by the controller 26. Thecontroller 26 then converts volume and specific gravity information to avalue of weight and compares it to the weight sensed by the load cell.Once the volume of the solution from the container 12 has beendelivered, pump 20 is deactivated by controller 26 and solutions fromthe container 14 and then the container 16 are then delivered inaccordance with the above discussion. When all the solutions have beendelivered, controller 26 senses a complete compounding operation andactivates alarm 108 on control panel 60.

Refer now to FIG. 4 which illustrates the use of two pumping modules,114 and 116 from separate bulk compounding systems acting in conjunctionwith one another to fill an individual receiving container in accordancewith the invention. As can be seen from the figure, pumping module 114is spaced above pumping module 116 so that laminar air flow can beenhanced around the sides of both pumping modules when laminar air isflowing from the back 118 to the front 120 of each module. In oneembodiment of the invention, the upper module 114 is spaced apart fromthe lower module 116 by at least one-sixth the height of the lowermodule. In other embodiments of the invention, the spacing between thetwo modules may be as great as the height of the lower module. In thepreferred embodiment of the invention, the distance between the twomodules is one third the height of the lower module.

As can be seen in FIG. 4, a first plurality of solution sources 122 isconnected to a single container 124 through a first plurality of fluidlines 126. Fluid through each fluid line is controlled by a separatepump 128-130 in a first pumping module. A second plurality of solutionsources 132 is connected to the container 124 through a second pluralityof fluid lines 134. Fluid through each of these sources is controlled bya separate pump in the second pumping module 116. The invention includesthe use of a connector means for connecting the output signals from thecontrol means for controlling the amount of fluid to be transferred fromeach of the solution sources 122 and 132 into the container 124. Theconnector means includes a multiplexer means which will be described ingreater detail below in a discussion relating to the electronics of theinvention.

FIG. 5 illustrates a front panel of the invention when two or more bulkcompounding systems are used in conjunction with each other. FIG. 5 canbe compared to FIG. 2 which illustrates a front panel of a single bulkcompounding system. As can be seen in FIG. 5, the front panel for usewith a multiple bulk compounding device includes a basic panel 136 andan add-on panel 138. The basic panel includes all the features of thefront panel described above for a single bulk compounding system. whilethe add-on panel 138 displays only volume and specific gravity for eachadditional set of source solutions controlled by a separate pumpingmodule. The interface between the add-on module 138 and the basic module136 will be described in greater detail below.

FIG. 6 illustrates one embodiment of the subject invention in which anovel manifold 140 is used to provide fluid communication throughmultiple sets of input lines 142 and 144 to a single output port 146. Ascan be seen in the figure, the manifold 140 includes a generallycylindrical housing 148 having a first plurality of radially extendinginput ports 150-156 in a first plane, and a second plurality of radiallyextending input ports 158-162 in a second plane. The angle formed by theintersection of the first and second planes may range from 60° to 120°.However, in the preferred embodiment, the angle formed by theintersection of the first and second planes is on the order of 90°. Inthe preferred embodiment of the subject invention, each of the inputports in the first plurality of input ports 150-156 is in the samehorizontal plane as a corresponding input port in the second pluralityof input ports 158-162. By locating corresponding input ports in thesame horizontal plane and by spacing the input ports close together, itis possible to significantly reduce the length of the cylindricalhousing to reduce the amount of fluid required to flush the cylindricalhousing when solution from one source is being changed to solution fromanother source. This is very important in the field of mixing solutionsfor hyperalimentation and other medical purposes because smalldiscrepancies in the amount of fluid actually transferred versus theamount of fluid desired to be transferred can have highly undesirableresults.

A major purpose of having the first plurality of input ports 150-156 atan angle from the second plurality of input ports 158-162 is illustratedin FIGS. 4 and 7. FIG. 7 also illustrates an important feature at theinvention which is to orient the outlet port 146 toward the back of apumping module when the manifold 140 is attached to the module andlaminar air flows from the back towards the front of the module. Theorientation of the manifold 140 as it is attached to the pumping module116 allows for laminar air flow at the outlet port 146, and by havingthe first plurality of input ports 150-156 at an angle with the secondplurality of input ports 158-162, laminar air flow is not disrupted atthe outlet port 146. Therefore, the chances of bacteria or other foreignbodies entering the container 124 through outlet port 146 are greatlyreduced. This is very important since the connection between container124 and outlet port 146 will be disrupted each time a new container 124is to be filled.

In another embodiment of the invention as illustrated in FIG. 8, themanifold 170 may have four separate sets of inlet ports 172-178. Eachset of inlet ports may be spaced generally 90° apart from the closestset of inlet ports on either side. FIG. 8 illustrates a top view of themanifold, so the individual inlet ports in each set is not illustrated.However, each set of inlet ports 172 would be in fluid communicationwith a common channel 180 similar to the configuration shown in FIG. 9for a two-set inlet port-type manifold 182. As can be clearly seen inFIG. 9, each inlet port 184 is in fluid communication with commonchannel 180 which, in turn, is in fluid communication with outlet port186. The embodiment illustrated in FIG. 8, having four separate sets ofinlet ports is useful when it is desired to combine four separatecompounding systems together to act in concert to fill a singlereceiving container. In other embodiments of the invention, it may bedesirable to combine three separate bulk compounding systems together.In that event, a manifold having three sets of inlet ports would bedesired, in which each set of inlet ports is spaced apart from the othersets by 120°.

Referring again to FIG. 9, as can seen in the preferred embodiment, eachinlet port 184 radially extends from a cylindrical housing 188 of themanifold 182. This embodiment is preferred because it greatly reducesthe volume of common channel 180 in the manifold.

While the mechanical features of combining two or more bulk compoundingsystems in accordance with the invention have been described above, itis important to fully understand how it is possible to electronicallyconnect two or more compounding systems so that they may act in concertto fill a single receiving container. The purpose of the discussionbelow is to enable one skilled in the art to combine two bulkcompounding systems in accordance with the invention.

Refer now to FIG. 10 which is a block diagram illustrating theelectrical connections for the input signals of two or more bulkcompounding systems used in conjunction with each other. As can be seenin the figure, two or more keyboards 200 and 202 for each bulkcompounding system is provided. Each keyboard 200, 202 in FIG. 10corresponds to the control panel 60 in FIG. 3. The output from eachkeyboard 204, 206 is fed into separate encoder modules 208 and 210. Thepurpose of each encoder module is to assimilate multiple signals fromeach keyboard into a series of binary signals. The output from eachencoder module 208, 210 is then connected together along data lines 212to be fed into a CPU interface circuitry 214. The CPU interfacecircuitry 214 illustrated in FIG. 10 enhances the control unit 26illustrated in FIG. 3. The CPU interface circuitry is unable todistinguish which encoder module has sent signals to the CPU without theuse of data lines 216 and 218. The presence or absence of a signal oneach of these data lines indicates which keyboard has been used to enterinformation into the CPU. Therefore, when a user of the presentinvention wishes to cause two or more of the bulk compounding systems tooperate in concert with each other to fill a single receiving container,the user simply inputs the amount of fluid to be transferred by eachsystem into that particular system's keyboard matrix. The CPU is thenable to receive the information from the keyboard matrix through theencoder and keep track of which pumping module is to be operated totransfer the fluids.

Refer now to FIG. 11 which is a block diagram illustrating theelectrical connection for multiple sets of output signals from two ormore bulk compounding systems for controlling each of the pumpingmodules for each bulk compounding system. As can be seen in FIG. 11, CPUinterface circuitry 214 also functions to control the motor of eachperistaltic pump in each pumping module for each bulk compoundingsystem. The CPU 214 performs this function by assimilating the datareceived from each keyboard matrix as discussed above, and creating afirst set of output signals 220 to be fed into multiplexer circuitry 222which will be discussed in greater detail below. The multiplexercircuitry 222 generates a plurality of sets of output signals 224 and226 to control two or more pumping modules 228 and 230. Each pumpingmodule contains a series of peristaltic pumps which are driven byindividual motors 232. The configuration illustrated in FIG. 11 isdesigned to be used with two pumping modules with three motors permodule. However, it is possible to expand this configuration to handlemore than two pumping modules with greater than or less than threeperistaltic pumps per module.

In order to better understand the method by which the signals aremultiplexed as illustrated in FIG. 11, it is necessary to refer now toFIG. 12, which is a schematic diagram of the block diagram in FIG. 11.As described above, the peripheral interface transmits output signals220 to the multiplexer circuitry 222. The multiplexer then converts theperipheral interface output signals to a plurality of binary levelsignals. The value of the sixteen output binary level signals isdirectly proportional to the total binary value of the four inputsignals from the peripheral interface output circuit. In this manner, itis possible for the four peripheral interface output lines toindividually turn on any one given motor. The output signals 224-226 arethen connected to each motor on/off circuit individually.

In order to turn on an individual motor 232, two conditions must occur.The first is that the opto-isolator 234 must be turned on. This isaccomplished by a low level output at the multiplexer. The secondcondition which must occur is that a second opto-isolator 236 must alsobe turned on at the same time. This is also accomplished by a low leveloutput at the multiplexer. With both opto-isolators simultaneouslyturned on, a current path is created allowing the motor turn on. To turnoff any individual motor, one or both of the opto-isolator outputs mustbe changed to a high level output.

Refer now to FIG. 13 which is a block diagram illustrating theelectrical connections for multiple sets of output signals from two ormore bulk compounding systems to display the precise amount of fluidstransferred by each bulk compounding system to a receiving container.The techniques for multiplexing display signals from the CPU 214 asillustrated in FIG. 13 is very similar to the techniques used above anddiscussed with respect to FIG. 11. As can be seen in FIG. 13, outputsignals 238 used to display the amount of fluid actually beingtransferred are sent from CPU 214 to multiplex/inverter circuitry 240.The purpose of the multiplex/inverter circuitry 240 is to assimilate thesignals received from the CPU 214 and generate a plurality of outputsignals 242, 244 to activate display circuitry modules 246 and 248 foreach bulk compounding system. A more detailed explanation of the mannerin which the signals are assimilated by multiplexer/inverter circuitry240 is discussed in greater detail with respect to FIG. 14 which is aschematic diagram of the block diagram of FIG. 13. As can be seen inFIG. 14, output signals 238 from the peripheral interface 214 are fedinto multiplexer 240. As can be seen in FIG. 14, in the preferredembodiment, only four input lines are used to relay information from theperipheral interface into multiplexer 240. The multiplexer 240 generatessixteen output signals based on this information. Each output signal isultimately used to generate a display on/off signal to indicate theamount of fluid that has been actually transferred on a display panel.The multiplexer 240 in FIG. 14 operates in a very similar manner to themultiplexer 222 in FIG. 12 as discussed above. That is, the multiplexer240 takes the total binary value of the signals received on input lines238 and generates sixteen output signals which are directly proportionalto the values received on the input lines. For simplicity, the detailsof the output signals for seven output lines of the multiplexer aredescribed in detail. As can be seen in FIG. 14, in order to turn on anindividual set of volume and specific gravity displays, a low outputvalue from the multiplexer is transmitted to an inverter 240 which inturn is transmitted to the display driver circuitry 250. At the displaydriver circuitry 250, the signal is again inverted and transmitted to adisplay driver. A low level signal at the display driver chip selectline turns on the display.

In conclusion, a key feature of the invention is that two or more bulkcompounding systems can be electrically connected to each other througha connector means which takes the total binary value of a relativelysmall number of input signals and generates a relatively large number ofoutput signals which are directly proportional to the received value. Inthis manner, it is possible to cause numerous pumping modules as well asdisplay modules on two or more bulk compounding systems to act inconcert with each other with minimal modifications to the internalelectronics of each unit.

Another key feature of the ivention is that the pumping modules for twoor more bulk compounding systems can be arranged and connected to oneanother using a novel manifold in a laminar flow hood in such a mannerto enhance laminar flow around the sides of each module and across theoutlet port of the manifold when laminar air is flowing from the back tothe front of each module.

Although the invention has been described and illustrated in detail, itis to be clearly understood that the same is by way of illustration andexample only, and is not to be taken by way of limitation; the spiritand scope of this invention being limited only by the terms of theappended claims.

That which is claimed:
 1. A device for connecting multiple bulkcompounding systems together in which each bulk compounding systemprecisely controls fluid transfer of at multiple solutions to a singlereceiving container, each solution being contained in a separate sourcecontainer, each bulk compounding system including:a manifold having anoutlet fluid line in fluid communication with said receiving container;a plurality of fluid lines, each source container being in fluidcommunication with one of said fluid lines each of said fluid linesbeing in fluid communication with said manifold; pumping means forpumping solution in said plurality of fluid lines from each of saidsource containers to said receiving container; control means, includingfirst means for sensing the weight of fluid in said receiving container,and second means including a peripheral interface means, said peripheralinterface means having a first set of input signals for selecting anamount of fluid to be transferred from each source container to saidreceiving container, said peripheral interface means also having a firstset of output signals for displaying the amount of solution to betransferred, and a second set of output signals for controlling saidpump means to deliver a predetermined amount of solution from saidsource to said receiving container in response to the amount of fluidsensed in said container, wherein the improvement comprises: firstelectronic connector means for electronically connecting together saidsecond set of output signals from more than one bulk compounding systemto cause said plurality of bulk compounding systems to transfer saidselected amount of fluids from said source containers to said singlereceiving container, said connector means having a multiplexer means forreceiving said second set of output signals from each of said bulkcompounding systems, and for generating a plurality of output signals toactivate said pumping means for each of said bulk compounding systems.2. A device as recited in claim 1, wherein:said pumping means includes aplurality of peristaltic pumps, each of said plurality of fluid lineshaving a peristaltic pump associated therewith for controlling the flowof fluid through said line; said second set of output signals for eachof said bulk compounders includes a plurality of binary signals, andsaid multiplexer means includes a means for converting each of saidplurality of binary signals into multiple binary signals in which thenumber of multiple binary signals corresponds to two raised to thenumber of said plurality of binary signals, each of said multiple binaryoutput signals corresponding to one of said each of said plurality ofbinary signals being directly proportional to the value of the totalbinary value of said multiple binary signals for controlling each ofsaid pumping means.
 3. A device as recited in claim 2, wherein saidsecond set of output signals for each of said bulk compounders includesfour binary output signals, said multiplexer means includes a means forconverting said four binary output signals into 16 binary outputsignals, each of said 16 binary output signals corresponding to one ofsaid pumps.
 4. A device as recited in claim 1, further including asecond connector means for connecting said first set of input signalsfrom each of said bulk compounding system to allow a user to inputsignals into more than one bulk compounding system to fill a receivingcontainer, said second connector means including a means for designatinga specific bulk compounding system for each of said first set of inputsignals.
 5. A device as recited in claim 1, further including a thirdconnector means for connecting said first set of output signals togetherto generate a series of display signals for more than one bulkcompounding system, said third connector means having a secondmultiplexer means for receiving said first set of output signals fromeach of said bulk compounding systems, and for displaying the amount ofsolution to be transferred for each specific bulk compounding system. 6.A device as recited in claim 5, wherein said said first set of outputsignals for each of said bulk compounders includes a plurality of binarysignals, and said second multiplexer means includes a means forconverting each of said plurality of binary signals into multiple binarysignals in which the number of multiple binary signals corresponds totwo raised to the number of said plurality of binary signals, each ofsaid plurality of binary signals being directly proportional to thevalue of the binary value of said multiple binary signals, each of saidmultiple binary output signals corresponding to a display signalrepresenting the amount of solution to be transferred from a specificbulk compounding system.
 7. A device as recited in claim 6, wherein saidfirst set of output signals for each of said bulk compounders includesfour binary output signals, said multiplexer means includes a means forconverting said four binary output signals into 16 binary outputsignals, each of said 16 binary output signals corresponding to adisplay signal representing the amount of solution to be transferredfrom a specific bulk compounding system.
 8. A device for connectingmultiple bulk compounding systems together in which each bulkcompounding system precisely controls fluid transfer of at least onesolution to a receiving container, each bulk compounding systemincluding:a plurality of solution source containers adapted to contain afluid solution; a manifold having an outlet line in fluid communicationwith said receiving container; a plurality of fluid lines, each sourcecontainer having one of said fluid lines in fluid communication withsaid manifold; pumping means for pumping solution in said plurality offluid lines from each of said plurality of solution source containers tosaid receiving containers; control means, including first means forsensing the weight of fluid in said container, and second meansincluding a peripheral interface means, said peripheral interface meanshaving a first set of input signals for selecting an amount of fluid tobe transferred from each source container to said receiving container,said peripheral interface means also having a first set of outputsignals for displaying the amount of solution to be transferred, and asecond set of output signals for controlling said pump means to delivera predetermined amount of solution from said source to said receivingcontainer in response to the amount of fluids sensed in said container,wherein the improvement comprises: a second electrical connector meansfor electrically connecting said first set of input signals to allow auser to input signals into more than one bulk compounding system to filla single receiving container, said second connector means including ameans for designating a specific bulk compounding system for each ofsaid first set of input signals.
 9. A device for connecting multiplebulk compounding systems together in which each bulk compounding systemprecisely controls fluid transfer of at least one solution to areceiving container, each bulk compounding system including:a pluralityof solution source containers adapted to contain a fluid solution; amanifold having an outlet line in fluid communication with saidreceiving container; a plurality of fluid lines, each source containerhaving one of said fluid lines in fluid communication with saidmanifold; pumping means for pumping solution in said plurality of fluidlines from each of said plurality of solution source containers to saidreceiving containers; control means, including first means for sensingthe weight of fluid in said container, and second means including aperipheral interface means, said peripheral interface means having afirst set of input signals for selecting an amount of fluid to betransferred from each source container to said receiving container, saidperipheral interface means also having a first step of output signalsfor displaying the amount of solution to be transferred, and a secondset of output signals for controlling said pump means to deliver apredetermined amount of solution from said source to said receivingcontainer in response to the amount of fluids sensed in said container,wherein the improvement comprises: third connector means for connectingsaid first set of output signals together to generate a series ofdisplay signals for more than one bulk compounding system, said thirdconnector means having a second multiplexer means for receiving saidfirst set of output signals from each of said bulk compounding systemsand for displaying the amount of solution to be transferred for eachbulk compounding system.